it's called the davey brown index. the poll tracks thousands of famous people across eight attributes including awareness, trust and influence. >> it's a must. >> reporter: brad pitt has a 98% awareness ranking. and out of nearly 3,000 celebrities, he's the 25th biggest influencer. morgan freeman is number eight. >> we are standing together for the right of gay and lesbian americans. >> reporter: in fact, of the ten celebrities currently ranked as the most influential, six are outspoken supporters of same sex marriage. >> i think that respect should be all across the board. >> reporter: with one in particular grabbing the most headlines. >> i think same sex couples should be able to get married. >> as a gay man, i got to tell you it just hit me right in my heart. >> reporter: so while it might be difficult to say exactly how much a star's opinion matters, there's no question they do have influence. and many of the world's most famous influencers support marriage equality. kareen wynter, cnn, hollywood. >>> and you're i